The present invention relates generally to the field of power electronic devices, and particularly to a novel technique for providing power to and from such devices in a modular package, and for providing cooling to the components, where desired.
A wide variety of applications exist for power electronic circuits, such as switching devices and systems. In such systems, multiple components may be combined and interconnected for a wide range of functionality. For example, in traditional switchgear applications, an enclosure is generally provided into which power is routed, along with network signals, sensor inputs, actuator outputs, and so forth. Components within the enclosure are interconnected with external circuitry, and can be interconnected with one another to provide for control, monitoring, circuit protection, and a multitude of other functions. Such conventional approaches, however, require a substantial number of terminations of various conductors, routing of conductors, mounting of various components, and so forth.
In other types of packaging, components may be associated with one another in mounting areas or bays, which are electrically coupled to buses for routing power to the various components. Examples of this type of packaging may be found in conventional motor control centers, in which various control, monitoring and protective circuits are mounted and interconnected with one another via wiring harnesses, cables, and so forth. In other applications, particularly where power levels are much lower, it has become conventional to provide a “backplane” to which components may be coupled, such as via plug-in connections. Such backplanes are currently in use throughout industrial applications, as for providing data and control signals to and from programmable logic controllers, computer components and peripherals, and so forth. The use of such backplanes, through which data and control signals can be easily routed, presents substantial advantages from the point of view of ease of assembly, replacement, servicing and expansion of overall systems incorporating a large number of interfaced components.
Despite the considerable convenience of backplane approaches to component interfacing, very limited use of such technologies has been made in power applications. In general, power applications may be considered to include those applications where higher power ratings are provided, typically either a single or three-phase ac power, to drive electrical loads. As will be appreciated by those skilled in the art, circuitry designed for such power applications typically differs substantially from circuitry for data applications. The power ratings, electrical characteristics, and thermal characteristics of power electronic circuits are particularly demanding, from many points of view. For example, due to higher voltage and current ratings, routing of conductors must meet stringent industry standards and codes. Dissipation of thermal energy in such settings is always an issue, particularly where package sizes become reduced due to space, weight and similar constraints. Certain circuits are currently cooled by fluids, including by liquid cooling media, which adds a further dimension to the complexity of mounting and routing of electrical conductors and fluid conduits.
Current interconnection arrangements for most power electronic circuits, like those for large motor drives, do not use backplane topologies. Rather, power is routed into, throughout and out of enclosures based upon the locations of the components. Coolant, if used, is similarly routed. Consequentially, it is common to see large conductors, insulated and uninsulated, bent into circuitous paths between and among components without much regard for the efficiency of the connections or the use of space. Such approaches are not only challenging to service, but can be quite time consuming to design and fabricate, generally requiring custom bending and installation of the many interconnections and supports.
There continues to be a need for improved techniques for mounting and interfacing power electronic components and products, that offer flexible and cost-effective manufacturing potential in modular packages. There is a particular need for improved designs for mounting and interconnecting power electronic components both electrically and with coolant sources that can be adapted for a wide range of applications and circuit configurations.